On October 18, it was confirmed by Japan's Japan Aerospace Exploration Agency (JAXA) that there is in fact a notable cave-like crater beneath the Moon's surface. Measuring to be 50 kilometers (31 miles) long and 100 meters (328 feet) wide, this crevasse, according to Japanese scientists, is "located beneath a region of volcanic domes known as the Marius Hills," and "may be a subterranean lava tube created by volcanic activity some 3.5 billion years ago." Discovered by Japan's Selenological and Engineering Explorer (SELENE) probe through the use of a radar system, this lunar fissure has already been proposed as a "possible candidate" for housing a lunar exploration base or human colony. Why? Because the structural stability of lava tubes make them the best solution for guarding against the before-mentioned crazy temperatures and cosmic radiation on the Moon's surface.